body {
  margin: 0px;
}

.fullpage {
  width: 100vw;
  height: 100vh;

  display: flex;
  /* 转换压力布局的方向为上下，而不是默认的左右 */
  flex-direction: column;
}

.center-box {
  flex: 1;
  overflow-y: auto;
}
